diff --git a/src/calibre/library/schema_upgrades.py b/src/calibre/library/schema_upgrades.py
index 2907e43098..a9cd36a588 100644
--- a/src/calibre/library/schema_upgrades.py
+++ b/src/calibre/library/schema_upgrades.py
@@ -606,6 +606,7 @@ class SchemaUpgrade(object):
         '''
 
         script = '''
+        BEGIN TRANSACTION;
         ALTER TABLE authors ADD COLUMN link TEXT NOT NULL DEFAULT "";
         '''
         self.conn.executescript(script)